1. Field of the Invention
The present invention relates to an antenna device including an antenna coil and an IC connected to the antenna coil, an antenna module including the antenna device, and a communication terminal apparatus.
2. Description of the Related Art
International Publication No. 2013/161608 discloses an antenna device including an antenna coil and an IC. The antenna device disclosed in International Publication No. 2013/161608 is configured such that the antenna coil is formed in a multilayer body, the IC is mounted on the multilayer body, and the IC is connected in parallel with the antenna coil.
In the antenna device disclosed in International Publication No. 2013/161608, the antenna coil and the IC are integrated with each other, so that it is possible to handle the antenna coil and the IC as one component. By mounting this component, for example, on a circuit board, an electronic apparatus supporting NFC (Near Field Communication), which is performed in the HF (high frequency) band, is configured.
However, regarding the antenna device in which the antenna coil and the IC are integrated with each other as disclosed in International Publication No. 2013/161608, the IC of the antenna device can operate even in a state of the antenna device as a single body before the antenna device is incorporated into an electronic apparatus. For example, during transport or the like of the antenna device, even in a state of the antenna device as a single body, when the antenna device comes close to a communication partner apparatus such as a reader/writer, the antenna coil magnetically couples with an antenna of the communication partner apparatus, and the IC operates, so that false information may be written into the IC.